IP Network Fundamentals

Legacy transport networks

• Distinguishing circuit and packet modes.
• Review: the challenges of voice transport.
• The transition to digital and the evolution of the telephone network.
• Synchronous transfer mode:
  • PDH and SDH digital hierarchies.
• Asynchronous transfer mode: ATM.

Introduction to TCP/IP

• The founding figures: Robert Kahn and Vinton Cerf.
• IP: 40 years of success — why did it become dominant?
• Founding principles: datagrams and interconnection; the TCP/IP protocol stack.
• Transfer modes: reliable/unreliable and connection-oriented/connectionless.
• The client/server model.
• The OSI reference model versus the TCP/IP model.
• RFCs, the role of the IETF and the standards track.

Internet layer protocols

• Adapting to the physical network: from IP over twisted pair to IP over SONET/SDH.
• IPv4, network addresses and subnet masks.
• Legacy addressing: address classes.
• CIDR and the move away from classes; VLSM masks.
• IPv6 addresses: structure, link-local, global and multicast addresses; interface identifiers and address life cycles.
• Subnetting by binary subdivision and aggregating networks: learning a quick, systematic method for IPv4 and IPv6.
• ICMP, IP's reporting protocol, and its main messages.
• The ping command and traceroute tool.

Practical work
Build a TCP/IP network with workstations, switches and routers, and configure the equipment. Generate ICMP packets and analyse them. Verify connectivity.

IP over LAN/MAN/WAN networks

• IP over LAN and MAN; associating an IP address with a MAC address; ARP requests.
• IP over ATM WAN; IP and ATM quality of service.
• MPLS: benefits and implementation principles.
• ADSL, VDSL, SDSL, xDSL and related technologies.

Practical work
Establish and verify connectivity between two remote IP networks.

The transport layer

• Protocol demultiplexing, movement up the layers and port numbers.
• TCP services: establishing a TCP connection; in-sequence transfer with acknowledgements and flow control.
• Safely closing a connection; window concepts and Slow Start.
• Connectionless mode: UDP and an example exchange.
• Sockets and the principles of network application design.

Practical work
Use an analyser to observe the phases of a TCP exchange.

Interconnecting IP networks

• The IP routing algorithm, routing tables and longest-prefix matching.
• Direct versus indirect routing.
• The router.
• Static versus dynamic routing; IGP versus EGP.
• Routing protocols and the main options.
• Distance-vector routing: RIP and EIGRP.
• Link-state routing: OSPF.
• Path-vector routing: BGP.
• Defining a gateway or default route.
• Address translation, public/private addresses and RFC 1918.

Implement a routing protocol on a topology of 3 or 4 routers. Testing and diagnostic tools and methods.

TCP/IP applications

• The name service: DNS; query resolution and domain name server network architecture.
• From the internet top level to the intranet domain.
• FTP: terminal and graphical modes.
• FTP commands, configuring an FTP server and security.
• HTTP and web applications.
• Email and SMTP, POP and IMAP.
• Telnet and SSH; securing access.
• Simple transfer with TFTP.

Practical work
Configure and perform an FTP file transfer using client software and a browser. Configure and perform a TFTP file transfer. Configure a DHCP server and a DNS server. Establish a remote-control session over IP.

TCP/IP network administration

• The components of a network management system.
• Collecting and analysing SYSLOG messages.
• Managing IP networks with SNMP: manager, protocol and MIB.
• Analysis tools.

Practical work
An administration example using SYSLOG. Use event-correlation software.

Towards IPv6

• Why a new protocol is needed; preparing for IPv6.
• Automatic configuration, global address formation with SLAAC, Neighbor Discovery, RS, RA, NS and NA messages, and the O and M flags.
• Stateless and stateful DHCPv6.
• IPv6/IPv4 coexistence tools: encapsulating IPv6 in IPv4, point-to-point tunnels, dynamic multipoint 6to4 tunnels, 6rd, NAT64 and DNS64.

Practical work
Apply an IPv6 addressing plan and implement SLAAC, DHCPv6 and IPv6 routing.

QoS — prioritising traffic

• Defining requirements. DiffServ and DSCP traffic marking. Solutions: traffic shaping and queuing; Fair Queuing, Priority Queuing and Custom Queuing.

Practical work
Configure different queue types and validate their impact on transfers.

Practical work arrangements
Each group of 2 participants administers at least one Cisco router and one switch.

Teaching methods
A balanced combination of presentations and workshops. During workshops, participants are guided by supporting documents that describe every operation.